High lift longitudinal axis control system

ABSTRACT

A bipartite, full span airplane flap system having an inboard flap portion and an outboard flap portion, wherein the outboard flap portion includes an integrated aileron mounted on its substantially equivalent spanwise length. The outboard flap portion is adapted to translate between a first and a second position to create a functional slot between a bottom surface of the flap member leading part and a bottom surface of the airfoil trailing part to draw a portion of higher pressure air from the bottom surface of the airfoil through the functional slot to distribute the higher pressure air over a top surface of the outboard flap portion.

RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 11/047,194, filed 31 Jan. 2005, now U.S. Pat. No.7,367,532 and entitled “High Lift Longitudinal Axis Control System,”which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

This invention relates generally to the aviation industry and morespecifically to a combination flap and aileron arrangement for improvingflight performance at low air speeds.

The desire to land at an airspeed as slow as possible while stillmaintaining adequate directional control is of ongoing concern in theaviation industry. The ability to maintain adequate airflow over flightcontrol surfaces, such as the ailerons, during slow flight such aslanding, increases the number of airports that can be used, but mostimportantly increases safety of operations. The development of efficientslow flight has included the use of highly cambered airfoils, hingedflaps, slots, spoilers, stall fences, and boundary layer controlsdevices such as vortex generators. The addition of one of these devicesadds to the initial cost and ongoing maintenance cost of the aircraft,the addition of multiple of these devices geometrically increasingcosts. The cost to benefit ratio limits the inclusion of thesemodalities on aircraft.

It is well known that trailing edge flaps on aircraft wings improveperformance of the aircraft, particularly in reducing landing speed whenthe flaps are adjusted to a position which increases wing camber. Thehighest flap utility is obtained when flaps are coextensive with thewing span. However, since ailerons are necessary to provide lateralcontrol of the aircraft, the flap portion is typically shortened on eachwing the amount necessary to accommodate the aileron. Variouscombinations have been devised endeavoring to maximize both flap andaileron efficiency, however none has been completely satisfactory.

The present invention offers a solution to this problem. The device ofthe present invention endeavors to lower the stall speed whileincreasing aileron authority in a cost effective manner. The inventioncombines the additional lift and laminar flow provided by knownFowler-style flaps with the increased efficiency of known Frise-typeailerons. The unique combination of the present device enables the Frisetype aileron component to create lift just as the wing does, andproduces greater lateral effect with less deflection of the control. Thepresent invention is further designed to decrease the wing tip vorticesat slower speeds, allowing the control to be placed closer to the wingtip where it can also augment its effect through a longer moment armwith less deflection.

SUMMARY OF THE INVENTION

The present invention relates to aircraft having one or more airfoils orwings including extensible flaps. A wing structure according to theinvention includes a novel flap assembly that serves in several respectsto improve the performance of an aircraft so fitted. The flap assemblyof the present invention consists of a combination of interrelatedairfoil elements, including flaps, which are arranged with respect toone another in various flight attitudes so as to give improved flightcharacteristics over known airfoils having flaps.

In general, the shape of a typical subsonic airfoil is designed toproduce a differential in air pressure between the upper and lowersurfaces, with the upper surface being subjected to a pressure lowerthan that on the lower surface. This differential produces a net effectof the wing rising toward the area of lower pressure. The reducedpressure experienced by the upper surface is dependent upon laminar flowover the surface. If the airfoil angle of attack is increased or theairfoil curvature is increased, the flow of air near the airfoiltrailing edge begins to separate and become turbulent. As the angle ofattack and/or the curvature is increased, the point at which separationoccurs moves forward on the airfoil, increasing the area of turbulence,until there is no differential in pressure between the upper and lowersurfaces of the airfoil, and no lift. The present invention seeks todecrease the total area of turbulent air by augmenting laminar flow overthe trailing edge of the airfoil during increased angles of attack andincreased curvature by way of a combination of slotted flap and anintegrated aileron assembly.

The flap elements of the present invention are of the type which aregenerally movable rearwardly and downwardly to thereby form a gap orslot between the trailing edge of the main airfoil and the leading edgeof the flap. The various elements of the present flap assembly aregenerally coextensive with main airfoil length and include an inboardflap portion and an outboard flap portion, the outboard portion beingfurther fitted with an integrated aileron.

The present invention provides an airfoil construction which includesthe use of substantially full span flaps to thereby reduce the stalling,landing and take off speeds. The airfoil of the present inventionfurther allows a more efficient aileron arrangement that permits maximumlateral control especially during slow airspeeds.

More specifically, the present invention provides an airfoil equippedwith a bipartite flap mechanism extending substantially the entirelength of the main airfoil. A flap mechanism according to the presentinvention includes an inboard flap portion and an outboard flap portionwhereby substantially the full length of the airfoil trailing edge maybe utilized. The invention further integrates the aileron within theoutboard flap portion.

One aspect of the invention provides an airfoil comprising a trailingpart and a full span, bipartite flap. The bipartite flap has a range ofpositions including an extreme retracted position and an extremeextended position, and the bipartite flap includes an inboard flapportion and an outboard flap portion. Each of the inboard flap portionand the outboard flap portion include a leading part and a trailingpart.

The outboard flap portion includes a flap member and an aileron member,the flap member having a flap member leading part and a flap membertrailing part having a fixed distance therebetween.

The aileron member is independently operable and pivotally mounted onthe flap member trailing part, the aileron member including an aileronmember leading part and an aileron member trailing part.

The airfoil includes linkage extending from airfoil support structure tothe outboard flap portion to translate the outboard flap portion betweenat least a first and a second position to create a functional slotbetween a bottom surface of the flap member leading part and a bottomsurface of the airfoil trailing part to draw a portion of higherpressure air from the bottom surface of the airfoil through thefunctional slot to distribute the higher pressure air over a top surfaceof the outboard flap portion.

The flap member trailing part of the outboard flap portion and all ofthe aileron member are adapted to be located aft of the airfoil trailingpart when the bipartite flap is in an extreme retracted position.

It is an object of the present invention to provide an airfoil for anairplane which will increase controllability and maneuverability of theairplane particularly in slow speed situations, without significantlyincreasing the complexity of design or execution of control.

It is a further object to provide such an airfoil to new airplanes or tomodify existing airplanes to improve their characteristics, as discussedabove, without significantly increasing the weight or cost of theairplane.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of an airplane with wings fitted with the flapcombination of the present invention.

FIG. 2 is a perspective view of an airplane wing fitted with thecombination of the present invention and showing the flaps and aileronin retracted and neutral positions, with the airplane shown in phantom.

FIG. 3A is a cross section of the wing shown in FIG. 2 and taken alonglines 3A-3A thereof, and showing the outboard flap portion.

FIG. 3B is a cross section of the wing shown in FIG. 2 and taken alonglines 3B-3B thereof, and showing the inboard flap portion.

FIG. 4A is a perspective view of an airplane wing fitted with thecombination of the present invention, similar to that of FIG. 2, butshowing the inboard flap extended approximately 30°, the outboard flapextended approximately 22° and the aileron in neutral position.

FIG. 4B is a cross section of the wing shown in FIG. 4A and taken alonglines 4B-4B thereof.

FIG. 5A is a perspective view of an airplane wing fitted with thecombination of the present invention, similar to that of FIGS. 2 and 4A,but showing the inboard flap extended approximately 30°, the outboardflap extended approximately 22° and the aileron reflexed approximately10°.

FIG. 5B is a cross section of the wing shown in FIG. 5A and taken alonglines 5B-5B thereof.

FIG. 6A is a perspective view of an airplane wing fitted with thecombination of the present invention, similar to that of FIGS. 2, 4A,and 5A but showing the inboard flap extended approximately 30°, theoutboard flap extended approximately 22° and the aileron deflecteddownward approximately −10°.

FIG. 6B is a cross section of the wing shown in FIG. 6A and taken alonglines 6B-6B thereof.

FIG. 7A is a diagrammatic view of a typical wing/control structure andillustrating the separation point of laminar flow and resultantturbulent flow which replaces it adjacent the wing and flap.

FIG. 7B is a diagrammatic view illustrating the airflow adjacent theoutboard flap and aileron combination of the present invention, with theposition of adjustment as shown in FIGS. 4A and 4B.

FIG. 8 is a partially cut away view of an airplane wing fitted with thecombination of the invention and showing a preferred activating system.

FIG. 9 is a partially cut away view of an airplane wing fitted with thecombination of the invention and showing an alternative activatingsystem.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention which may be embodied inother specific structures. While the preferred embodiment has beendescribed, the details may be changed without departing from theinvention, which is defined by the claims.

FIG. 1 of the drawings illustrates an airplane 10 having a fuselage 12and wing structure comprising a right wing structure 14A and a left wingstructure 14B. The main airfoil of each wing structure 14A, 14B isdesignated by the numeral 16.

Each of the main airfoils 16 includes a leading edge 18 and a trailingedge 20. Each wing structure 14A, 14B further preferably includes aninboard flap portion 22 and an outboard flap portion 24, each of theflap portions 22, 24 having a flap leading edge 26A, 26B, respectively,and a flap trailing edge 28, with the respective flap leading edges 26A,26B each being located adjacent the airfoil trailing edge 20. Each flapleading edge 26A, 26B is preferably capable of movement with respect toits respective flap trailing edge 28. As seen, the outboard flap portion24, is preferably comprised of a flap member 29 having an aileron 30pivotally mounted on its flap member trailing edge 27.

As may be seen particularly in the views of FIGS. 2, 3A, and 3B, theinboard flap portion 22 is preferably comprised of a fowler-style flapand is so mounted on each respective main airfoil 16 such that it isrotatable over a limited arcuate range on a spanwise axis, and may beprojected fully rearwardly to an extended position as shown in FIGS. 4Aand 6A. As may be seen in FIG. 4A, when the inboard flap 22 is projectedrearwardly and downwardly a slot 32 is provided between the trailingedge 20 of the main airfoil 16 and the flap leading edge 26A. Theoutboard flap portion 24 is preferably comprised of a flap member 29 andan inset aileron member 30, such as the Frise-style aileron shown. It isto be understood that while Frise-style ailerons are preferred tothereby minimize adverse yaw and the need for differential deflection ofailerons, other known aileron types may be used. The present arrangementprovides maximum lift coefficient while maintaining aileron control atlower speeds.

As may be seen particularly in the views of FIGS. 4B, 5B, and 6B, duringoutboard flap 24 extension a secondary slot 34 is formed between theflap leading edge 26B and the trailing edge 20 of the main airfoil 16.As illustrated particularly in the view of 7B, and as discussed above,the secondary slot 34 functions, similarly to that of slot 32, to draw aportion of higher pressure air from the bottom surface 36 of the airfoil16, through the secondary slot 34 and distribute it in laminar flow overthe top surface 38 of the outboard flap portion 24, consisting of flapmember 29 with its integrated aileron 30. This action thereby augmentsthe laminar air flow of the total wing structure 14A, 14B and increasesthe net lift of the wing structure 14A, 14B through the contribution oflift exerted by the outboard flap portion 24 including the flap member29 and its integrated aileron 30. This effect is contrasted with theconventional wing 40 illustrated in FIG. 7A. As may be seen, lift isgenerated forward of the separation point 42, with the trailing edge 44of the wing structure 40 and the aileron 46 unable to contribute to theoverall lift of the wing structure 40 due to the area of turbulence 48located adjacent those structures. It is to be noted that in addition tothe benefits previously discussed, the present arrangement minimizesaileron 30 deflection and size, since laminar airflow is maintained overa substantial area of the aileron 30 surface, allowing it to produce anet moment by means of both displacement and lift. Additionally, generalcontrol efficiency is enhanced, since the adverse effect of wing tipvortices at high angles of attack is reduced.

Illustrated in FIG. 8 is a preferred manner in which the flap system ofthe present invention is mounted on the wing structure 14A, 14B andoperated. As seen, a linear actuator 50, including a jackscrew 52motivated by a prime mover, such as the electric motor 54 shown, isultimately activated by conventional pilot control means. The actuator50 is connected to a cable 56, movement of which ultimately moves bothinboard flaps 22 and outboard flap members 29, respectively. The cable56 is supported by idler pulleys 58 and a drive pulley 60. The drivepulley 60 is further attached to a bellcrank 62 having arms 64A, 64B.Rotation of the drive pulley 60 moves the bellcrank arms 64A, 64B andtheir pivot pins 66A, 66B. Attached to each bellcrank arm 64A and itsrespective pivot pin 66A is the first end 68 of linkage arm 70. Thesecond ends 72 of each linkage arm 70 are conventionally pivotallyattached to a respective leading edge 26A, 26B of the outboard flapmember 29 or inboard flap 22. The bellcrank arms 64B are each pivotallyattached to an axially reciprocating moveable rod 74, which extendssubstantially spanwise of the wing structure 14A, 14B. Outboard flapmember 29 and inboard flap 22 move in accordance with the contour ofcammed internal flap tracks 76, shown. It is to be understood thatalthough conventional internal flap tracks 76 are shown in this view, insome applications, the invention contemplates the use of externallinkage operated flaps tracks (not shown). The aileron member 30 of thepresent invention is conventionally moved independently by push pulltubes 78 and is operated by the pulley system A, shown in FIG. 8, orother known means.

FIG. 9 illustrates an alternative operational system for the presentinvention, in which the bellcrank 62 and pulley 58, 60 flap drivemechanism shown in FIG. 8 has been replaced by a torque tube drivesystem B. The torque tube drive system B preferably utilizes a primemover, such as the motor 54 shown in phantom.

It is to be understood that the right wing structure 14A on the rightside of the plane has similar and similarly mounted and related parts.

The foregoing is considered as illustrative only of the principles ofthe invention. Furthermore, since numerous modifications and changeswill readily occur to those skilled in the art, it is not desired tolimit the invention to the exact construction and operation shown anddescribed. While the preferred embodiment has been described, thedetails may be changed without departing from the invention, which isdefined by the claims.

1. An airfoil comprising: a trailing part and a full span, bipartiteflap, said bipartite flap having positions including an extremeretracted position and an extreme extended position; said bipartite flapincluding an inboard flap portion and an outboard flap portion; each ofsaid inboard flap portion and said outboard flap portion including aleading part and a trailing part; said outboard flap portion including aflap member and an aileron member, said flap member having a flap memberleading part and a flap member trailing part having a fixed distancetherebetween; said aileron member being independently operable andpivotally mounted on said flap member trailing part, said aileron memberincluding an aileron member leading part and an aileron member trailingpart; linkage extending from airfoil support structure to said outboardflap portion to translate said outboard flap portion between at least afirst and a second position to create a functional slot between a bottomsurface of said flap member leading part and a bottom surface of saidairfoil trailing part to draw a portion of higher pressure air from saidbottom surface of said airfoil through said functional slot todistribute said higher pressure air over a top surface of said outboardflap portion; and said flap member trailing part of said outboard flapportion and all of said aileron member being located aft of said airfoiltrailing part when said bipartite flap is in an extreme retractedposition.
 2. The airfoil of claim 1 further including: means forimparting relative movement between the leading and trailing part ofeach of said inboard flap portion and said outboard flap portion.
 3. Theairfoil of claim 2 wherein said means for imparting relative movementcomprises: at least a first linkage member and a second linkage member,each of said first linkage member and said second linkage member beingdisposed for reciprocating push pull movement transversely relative to asubstantially spanwise axis of said airfoil, each respective firstlinkage member and said second linkage member having a first end and asecond end, said first end of said first linkage member being pivotallyattached to said inboard flap leading part and said first end of saidsecond linkage member being pivotally attached to said flap memberleading part for reciprocal movement of said flap member leading partand said inboard flap leading part relative to said spanwise axis; apivotally operable bell crank lever including a pair of normallydisposed, bifurcated arms, the second end of at least one of said firstlinkage member and said second linkage member being pivotally attachedto one of said arms; said bellcrank member including another armpivotally attached to an operating rod, said operating rod beingarranged for reciprocating axial movement for pivotal operation of saidbellcrank and consequent reciprocating axial movement of said linkagemember.
 4. The airfoil of claim 2 wherein said means for impartingrelative movement comprises: a rotatably-operated, elongated, torquetube extending spanwise of said airfoil; and at least a first linkagemember and a second linkage member, each of said first linkage memberand said second linkage member being disposed for reciprocating pushpull movement transversely relative to a substantially spanwise axis ofsaid airfoil, each respective first linkage member and said secondlinkage member having a first end and a second end, said first end ofsaid first linkage member being pivotally attached to said inboard flapleading part and said first end of said second linkage member beingpivotally attached to said flap member leading part for reciprocalmovement of said flap member leading part and said inboard flap leadingpart relative to said spanwise axis; the second end of at least one ofsaid first linkage member and said second linkage member being pivotallyattached to said torque tube and rotatably moveable therewith.
 5. Theairfoil of claim 4: further including control means for said means forimparting relative movement.
 6. The airfoil of claim 1: furtherincluding control means for said means for imparting relative movement.7. The airfoil of claim 6 wherein said control means for said means forimparting relative movement comprises: a reciprocally moveable linearactuator; and a prime mover for operating said linear actuator.
 8. Theairfoil of claim 7: wherein said means for imparting relative movementincludes a pulley-operated, endwise movable, cable having a first endand a second end; said cable being supported by a drive pulley and beingattached at each of said first end and said second end to arcuatelyspaced locations on said drive pulley, said cable being further moveablysupported by spaced apart idler pulleys and being attached to saidlinear actuator for reciprocal movement therewith.
 9. An airplane wingcomprising: a main airfoil, said main airfoil having a leading edge anda trailing edge; a full span flap structure, said full span flapstructure including an inboard flap portion and an outboard flapportion; said inboard flap portion having an inboard flap leading edgeand an inboard flap trailing edge; said inboard flap leading edge beingmovably located adjacent said trailing edge of said main airfoil; saidoutboard flap portion being partitioned spanwise to provide a flapmember and an aileron member, said flap member having a flap memberleading edge and a flap member trailing edge having a fixed distancetherebetween; said flap member leading edge being movably locatedadjacent said trailing edge of said main airfoil, said aileron memberbeing pivotally mounted adjacent to said flap member trailing edge;adjustable mounting means on said wing for said full span flapstructure; and control means for said adjustable mounting means toselectively move the respective axis of each of said outboard flapportion and said inboard flap portion in a generally aft andsubstantially downward direction to positions between and including anextreme retracted position in which said flap member trailing edge ofsaid outboard flap portion and all of said aileron member are locatedaft of said airfoil trailing edge, and an extreme extended position ofsubstantial aft displacement of the inboard flap structure and theoutboard flap structure from the main airfoil in which said inboard flapleading edge and a substantially spanwise portion of said trailing edgeof said main airfoil cooperate to form a first slot therebetween, andsaid flap member leading edge and a substantially spanwise portion ofsaid trailing edge of said main airfoil cooperate to form a second slottherebetween, the second slot comprising a functional slot between abottom surface of said outboard flap portion and a bottom surface ofsaid trailing edge of said main airfoil to draw a portion of higherpressure air from the bottom surface of said main airfoil through thesecond slot to distribute the higher pressure air over a top surface ofsaid flap member and said aileron member.
 10. The airplane wing of claim9 wherein said adjustable mounting means comprises: at least a firstlinkage member and a second linkage member, each of said first linkagemember and said second linkage member being disposed for reciprocatingpush pull movement transversely relative to a substantially spanwiseaxis of said wing, each respective first linkage member and said secondlinkage member having a first end and a second end, said first end ofsaid first linkage member being pivotally attached to said inboard flapleading edge and said first end of said second linkage member beingpivotally attached to said flap member leading edge for reciprocalmovement of said flap member leading edge and said inboard flap leadingedge relative to said spanwise axis; a pivotally operable bell cranklever including a pair of normally disposed, bifurcated arms, the secondend of at least one of said first linkage member and said second linkagemember being pivotally attached to one of said arms; said bellcrankmember including another arm pivotally attached to an operating rod,said operating rod being arranged for reciprocating axial movement forpivotal operation of said bellcrank and consequent reciprocating axialmovement of said linkage member.
 11. The airplane wing of claim 9wherein said control means for said adjustable mounting means comprises:a reciprocally moveable linear actuator; and a prime mover for operatingsaid linear actuator.
 12. The airplane wing of claim 11: wherein saidadjustable mounting means includes a pulley-operated, endwise movable,cable having a first end and a second end, said cable being supported bya drive pulley and being attached at each of said first end and saidsecond end to arcuately spaced locations on said drive pulley, saidcable being further moveably supported by spaced apart idler pulleys andbeing attached to said linear actuator for reciprocal movementtherewith.
 13. The airplane wing of claim 12: wherein said drive pulleyis further attached to a bellcrank lever.
 14. The airplane wing of claim9 wherein said adjustable mounting means comprises: arotatably-operated, elongated, torque tube extending spanwise of saidwing; and at least a first linkage member and a second linkage member,each of said first linkage member and said second linkage member beingdisposed for reciprocating push pull movement transversely relative to asubstantially spanwise axis of said wing, each respective first linkagemember and said second linkage member having a first end and a secondend, said first end of said first linkage member being pivotallyattached to said inboard flap leading edge and said first end of saidsecond linkage member being pivotally attached to said flap memberleading edge for reciprocal movement of said flap member leading edgeand said inboard flap leading edge relative to said spanwise axis; thesecond end of at least one of said first linkage member and said secondlinkage member being pivotally attached to said torque tube androtatably moveable therewith.
 15. The airplane wing of claim 14: whereinsaid control means comprises a prime mover arranged to alternativelyrotate said torque tube.
 16. An airfoil having a trailing edge and afull span, bipartite flap, said bipartite flap having positionsincluding an extreme retracted position and an extreme extendedposition, said bipartite flap adapted to translate between a first and asecond position to create a functional slot between a bottom surface ofa leading part of said bipartite flap and a bottom surface of theairfoil trailing edge to draw a portion of higher pressure air from thebottom surface of the airfoil through the slot to distribute the higherpressure air over a top surface of the bipartite flap; said bipartiteflap including an inboard flap portion and an outboard flap portion;said inboard flap portion including an inboard flap portion leading edgeand an inboard flap portion trailing edge; said outboard flap portionincluding an outboard flap portion leading edge and an outboard flapportion trailing edge; said outboard flap portion including a flapmember and an aileron member, said flap member having a flap memberleading edge and a flap member trailing edge having a fixed distancetherebetween, said aileron member having an aileron member leading edgeand an aileron member trailing edge; said aileron member being pivotallymounted such that said aileron member leading edge is located adjacentsaid flap member trailing edge; and said flap member trailing edge ofsaid outboard flap portion and all of said aileron member being locatedaft of said airfoil trailing edge when said bipartite flap is in anextreme retracted position.
 17. The airfoil of claim 16: furtherincluding means for imparting relative movement between the leading andtrailing edge of each of said inboard flap portion and said outboardflap portion.
 18. The airfoil of claim 17 wherein said means forimparting relative movement comprises: at least a first linkage memberand a second linkage member, each of said first linkage member and saidsecond linkage member being disposed for reciprocating push pullmovement transversely relative to a substantially spanwise axis of saidairfoil, each respective first linkage member and said second linkagemember having a first end and a second end, said first end of said firstlinkage member being pivotally attached to said inboard flap leadingedge and said first end of said second linkage member being pivotallyattached to said flap member leading edge for reciprocal movement ofsaid flap member leading edge and said inboard flap leading edgerelative to said spanwise axis; a pivotally operable bell crank leverincluding a pair of normally disposed, bifurcated arms, the second endof at least one of said first linkage member and said second linkagemember being pivotally attached to one of said arms; said bellcrankmember including another arm pivotally attached to an operating rod,said operating rod being arranged for reciprocating axial movement forpivotal operation of said bellcrank and consequent reciprocating axialmovement of said linkage member.
 19. The airfoil of claim 17: furtherincluding control means for said means for imparting relative movement.20. The airfoil of claim 19 wherein said control means for said meansfor imparting relative movement comprises: a reciprocally moveablelinear actuator; and a prime mover for operating said linear actuator.21. The airfoil of claim 20: wherein said means for imparting relativemovement includes a pulley-operated, endwise movable, cable having afirst end and a second end, said cable being supported by a drive pulleyand being attached at each of said first end and said second end toarcuately spaced locations on said drive pulley, said cable beingfurther moveably supported by spaced apart idler pulleys and beingattached to said linear actuator for reciprocal movement therewith. 22.The airfoil of claim 21: wherein said drive pulley is further attachedto a bellcrank lever.
 23. The airfoil of claim 17 wherein said means forimparting relative movement comprises: a rotatably-operated, elongated,torque tube extending spanwise of said airfoil; and at least a firstlinkage member and a second linkage member, each of said first linkagemember and said second linkage member being disposed for reciprocatingpush pull movement transversely relative to a substantially spanwiseaxis of said airfoil, each respective first linkage member and saidsecond linkage member having a first end and a second end, said firstend of said first linkage member being pivotally attached to saidinboard flap leading edge and said first end of said second linkagemember being pivotally attached to said flap member leading edge forreciprocal movement of said flap member leading edge and said inboardflap leading edge relative to said spanwise axis; the second end of atleast one of said first linkage member and said second linkage memberbeing pivotally attached to said torque tube and rotatably moveabletherewith.